A variety of lift devices are known in the prior art for moving invalid or handicapped person from one position to another. In fact, there are several devices disclosed in the prior art which have been found useful specifically for moving persons from the poolside to the pool and back again, or movement to and from a bathtub and the like.
Such devices suffer from flaws in operation, safety, or convenience and the inventor herein, familiar with such devices as a result of having worked in the field for several years, noted these flaws and devised a series of apparati which tend to overcome most, if not all, of such shortcomings.
One such device, and a device believed by the inventor herein as being the closet prior art device, can be found in U.S. Pat. No. 4,996,728, which issued Mar. 5, 1991 to John Nolan. The nolan device is hydraulically powered and is mounted near the pool edge. However, the Nolan device is comprised of a stabilized single post mounted on a solid substrate, and a hydraulic piston driven assembly which is rigidly mounted to the single post. The lifting chair, attached to the piston shaft has a capability of swinging in a limited arc, to bring the lift chair from the solid substrate to a position over the water, which then allows the piston to drive the lift chair in a downwardly motion. This device requires that the occupant must load and unload very near the edge of the pool, contributing to the advent of accidents.
Most significantly however is the fact that the device of Nolan does not have the movement of the lift chair within the immediate control of the occupant at all times and therefore, the occupant may be unable to stop or reverse it until the end of its travel.
The inventor herein also wishes to note for those skilled in the art that there exists a U.S. Pat. No. 5,383,238, in the name of the inventor herein, which issued on Jan. 24, 1995, in which there is shown a lift device that is electrically powered and which has an electromagnetic brake to control the movement of the lift chair.